Gil, not true.
RECFM=U was used by OBS/ACS WYLBUR to be as efficient as possible
with disk. So unless told otherwise, WYLBUR would save your
source or data in RECFM=U files. Further, it would do compaction
when it ran into an out of space problem, and it would do it so
that the DSN in question would be a single extent at the end of
the process.
I do not know if ROSCOE or EDGAR (I think it was a different
product whose name I can't remember right now) also did RECFM=U
or not, for the same reasons.
If the DSN were RECFM=FB (for instance), then WYLBUR would honor
that.
Don't ask me all the particulars of how WYLBUR did all this
because I haven't touched WYLBUR internals since about 2000.
Regards,
Steve Thompson
On 04/13/2016 08:14 PM, Paul Gilmartin wrote:
On Wed, 13 Apr 2016 23:54:58 +0000, Savor, Thomas (Alpharetta) wrote:
I've run into another PDSe problem.
When I was reading through a PDS file of Source Code, I would define DCB as
RECFM=U,
After the OPEN, DCBLRECL = Record Length. DCBBLKSI = File Block Size
After issuing a READ, DCBLRECL would be the Actual Block Size.
My PDS : LRECL=80, BLKSIZE=27920 Number of records per block = 349
So if a program has 500 lines of code:
First read DCBLRECL would = 27920, Number of lines would = 349
Next read DCBLRECL would = 12080, Number of lines would = 151
Maybe it was an accident, but this has worked for me forever.
Now same program using same DCB definition, determines than it's a PDSe before
the OPEN.
If it's a PDSe, program changes RECFM to be FB....which returned a full block
of records.
How do I tell when the difference between a full block and a short block on a
PDSe ??
Hope I explained this right.
I don't think block boundaries mean much to a PDSE which keeps everything in
4KiB pages.
You can override with any DCBBLKSI from 80 to 27920 and a READ will fetch enough
records to fill that block.
Customarily, RECFM=U indicates a Program Object. Perhaps PDSE enforces this.
What are you trying to do?
-- gil
Thanks,
Tom Savor
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